Conventionally, urethane foam has been widely used as a cushioning material for seats and the like, and commonly used is one combined with a reinforcing material when a molded urethane foam body is formed. The reinforcing material is interposed between a molded urethane foam body and a metal spring, and plays roles of distributing cushioning effect of the metal spring as well as protecting the molded urethane foam body from friction arising from the metal spring. As the quality required by consumers is becoming higher, there has been a growing demand for eliminating fricatives generated by friction between urethane which has leaked into the reinforcing material and the metal spring, and as a reinforcing material responding to the demand, a reinforcing material having a bulky layer and a dense layer wherein the dense layer prevents leakage of urethane is proposed (for example, refer to Patent documents 1 and 2). However, problems are that, since such a reinforcing material has insufficient formability when forming urethane foam, if urethane foam having a highly uneven shape with high design quality which is in high demand in recent years is used for a molded body, such defects as wrinkling and breakage are formed, from which the leakage of urethane and the friction with the metal spring arise. Therefore, a reinforcing material using elastomer and the like which is flexible and can be used for forming urethane foam having a highly uneven shape is proposed (for example, refer to Patent document 3). However, the reinforcing material has problems of insufficient productivity and handleability. Namely, as a process for producing a reinforcing material, a few dozen layers of nonwoven fabric are piled up for stamping, and while the stamped nonwoven fabric is sewn by hand into a desired shape, the number of pieces to be piled during stamping is limited in production of a flexible nonwoven fabric using elastomer and the like, and variation of shapes becomes large and sewing becomes inaccurate, resulting in problems of productivity and quality.
[Patent document 1] Japanese unexamined patent publication No. 6-171002
[Patent document 2] Japanese unexamined patent publication No. 6-171003
[Patent document 3] Japanese unexamined patent publication No. 2004-353153